Keyhole guard



Aug. 11, 1926. 1,596,711

F. c. BONIFACJO KEYHOLE GUARD V Filed August 16, 1924 2 Sheets-Sheet 1 ZIZzI? Q Z.

V Patented Aug, 17, 1926.

1,596,711 ICE.-

FERNANDO o. IBONIFACIO, or SAN FRANCISCO, CALIFORNIA.

K EYHOLE GUARD.

Application filed August 16, 1924.

This invention relates to improvements in looks and more particularly for guards to be mounted upon door locks and the like.

An important object of the invention is to provide a keyhole guard which may be securely positioned against the keyhole of a door lock or the like and prevent opening of the same.

A further object of the invention is the provision of a device of this character which. may be positioned on either side of the door lock and prove equally effective in either position. V

A still further object of the invention is the provision of a movable keyhole guard of this character which may be easily locked in position and also readily removed.

Other objects and advantages of this invention will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout the same:

Figure 1 is a front elevation of my improved device,

Figure 2 is a sideelevation showing the device mounted in position on a door lock,

Figure 3 is a rear elevation of the device,

Figure 41 is a front elevation, parts being broken away to show the interior construction thereof,

Figure 5 is a vertical sectional view taken onthe line 5-5 of Figure .4, V

Figure 6 is an enlarged detail View of the locking device, and Q V Figure .7 is a horizontal sectional view taken on the line 77 of Figure 4.

In the drawings, wherein for the purpose of illustrat'ion is shown the preferred em-' bodiment of my invention, the numeral 10 generally indicates the body or casing of my improved guard, this body comprising an end plate 11 and side walls 12. The body is substantially rectangular in shape and is provided in one extremity thereof with a partition plate 13, this plate forming a comparatively narrow compartment 14 at one extremity of the body.

Rigidly secured to the inner side of the end plate 11 and positioned approximately in the center thereof is a key pin 15, this pin being somewhat longer than the width of the casing, causing the same to project substantially therethrough. This pin is adapted to receivea suitable key thereon 'sitioned for unlocking upon a rivet 23.

Serial No. 732,481.

and thereby causing the key to be suitably pothe mechanism. A pin member 16 is secured to the outer side of the end plate 11, this pin being preferably positioned near the upper central portion thereof and adapted to engage the keyhole of the door look. This pin should be of sufficient length to penetrate the greater portion of the keyhole thereby preventing the insertion of a key therein. An extension lug 17 is formed upon the pin 16 adjacent the end plate 11, this lug being preferably formed upon the side of the pin nd adapted to when the same is locked in position. hen the guard is secured upon a door lock it is obvious that the lug 17 will prevent forcible removal of the guard, the extension lug engaging the outer lock plate and preventing disengagement of the pin 16.

similar projecting guide same during its rotary movement,

prevent removal of the guard Positioned horizontally in the upper portion of the casing and secured to the partition plate 13 mounted therein, is a guide pin 18, this pin being adapted to extend substantially across the inner portion of the casing and slidably support a lock bar 19.

The lock mar 19 comprises a substantially rectangular body 20 having formed through the greater portion thereof a longitudinal slot 21, this slot being provided to enable the lock bar to slide upon the guide pin 18. One extremity of the guide bar is provided with a tapered extremit' 22, the lower portion of this extension being somewhat narrower than the body 20 and adapted to slide The other extremity of the lock bar is provided with a downwardly extending plate 24:, this plate being substantially the same Width as the lock bar body and adapted to be actuated by the key extension. A coiled spring 25 is positioned about the guide pin 18 and is adapted to force the lock bar 19 toward one side of the casing, that is, plate 13.

The upper side of the casing 10 is provided with a pair of openings 26 formed near the extreme ends thereof and adapted to receive therein the lower end of a hasp or yoke 27.

The hasp or yoke shaped, the upper or comparatively narrow and adapted to engage the shaft of a door knob, the inter- 27 is substantially U- away from the partition neck portion 28 being I mediate portions diverging outwardly as i shown at 29 and carrying a comparatively short leg 30 and a longer leg 31. These legs are adapted to be inserted through the openings 26 formed in the upper portion of the casing and lock the guard securely upon the door lock. The inner side of the short leg 80 is serrated at the lower portion thereof to form toothed members 32. these members being adapted to engage the tapered extension of the lock bar and prevent removal of the hasp when the bar is in the es:- treme position. The long leg 31 of the hasp is provided with a cap 33 formed on the lower extremity thereof and adapted to prevent removal of the hasp in the extreme upward position of the same, the cap extend ing about the lower portion of the leg and being of greater diameter than the opening 26 formed in the casing. l v hen the hasp is in the extreme upward position it is ohvious that the hasp may be readily rotated but-prevent disengagement with the casing,

The front portion of the casing 10 is en closed by a removable end plate 3%, this plate being secured to the side of the casing by means of rivets S5 or in any suitable manner.

In use, the device may be readily em ployed upon the usual form of door locks,

being equally eflicient when mounted upon the inner or outer side thereof. To secure the guard in position upon a door look a 1 suitable key is positioned upon the key pin 15 and insert d through the opening 86 formed in the removable end plate 34:. w hen the key'is rotated in a clockwise direction the evtension thereon will engage the plate 52 i formed on the lock bar, causing the said lock bar to slidably move in the direction of the partition plate 13. When the loci: bar is moved toward the partition sideof the easing the extension 22 will be disengaged from the toothed members formed upon the hasp leg 30 thereby leaving the hasp to readily drawn upwardly and entirely free th shortleg 30. The hasp or yoke '27 is then positioned over the door knob shaft. and the projecting pin 16 inserted in the keyhole of the door lock. lhe short leg of the hasp is then forced through the opening'26 and the haspforced tightly into the guard casing, the lock bar being forced to engage the teeth formed onthe leg 30 by means" ofthe spring 25. VVhen' the hasp has been tightly forced nto the casing it w ll be securely retained therein until released by the key member,

the guaiwjl being tans securelypositioned against the keyhole. The projecting lug 17 formed upon the pin 16 will engage'the inner side ofthe lock plate and prevent forcible removal of theguard.

It is to be understood that the form of my invention herewith shown and described is to be taken as the preferred example of the same, and that various changes as to the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention, or the scope of the subjoined claims.

-Ha-ving thus "described my invention, I claim:

1. A keyhole guard comprising a substantially rectangular body composed of end plates, and side walls, a partition plate mounted adjacent one of the said side walls, a projecting pin formed on the outer side of one of the end plates, a key pin mounted on the inner side of the said plate and a guide pin horizontally mounted in the uppe portion of the said casing; an L-shaped locking bar having a longitudinal 7 slotformed therein adapted to slide upon the said guide pin, and a tapered extension formed on one end of the saidlock bar; and a hasp con'iprising a'eomparatively reduced neck portion, the intermediate portion of the hasp diverging, extension legs formed on the lower portion of the said hasp, toothed membersformed on one of the said legs, and a retaining cap formed upon the other leg. r

2. A keyhole guard comprising a body or easing having a" pair of end plates, side walls, a vertical partition plate adjacentone of the said side walls, a projecting pin formed on the outer side of one of the said plates, a key pin formed on the inner side ofone of the endplates, a horizontal guide pin formed on the said partition plate, and means for securely fastening the saidend plates; a substantially U-shaped hasp comprising a substantially narrow neck member formed on the upper portion thereof, the intermediate portion thereof diverging and carrying on the lower extremities thereof a pair of leg members, one of the saidleg members being comparatively short and having toothed members formed 'onfthe inner side thereof, while theother leg member is provided with a cap; a lock bar having a longitudinal slot formed therein, onejextremity of the said lock bar being tapered to engage the teeth formed upon the shortleg of the hasp, an extension plate formed on the outer. extremity of the bar, and,means; for support-ingthe bar, and a coiled spring member positioned about the guide pin for forcing the said locking barftoward the toothed leg of the hasp.. v

Intestimony whereof, Ih'ave aflixed-my signature.

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